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Faulty forensic testing convicted Maguire Seven

By MICK HAMER

Sloppy laboratory practice helped to convict members of the Maguire
family, a leading forensic scientist said, following the disclosure in the
Court of Appeal that test kits used to detect traces of explosives were
contaminated.

At the Old Bailey in 1976, six members of the Maguire family and a friend
were convicted of running an IRA bomb factory in north London on the basis
of forensic evidence, and sentenced to up to 14 years in jail. Scientists
told the court in 1976 that the seven had been ‘kneading’ nitroglycerine.
The last of the Maguire Seven was released from prison in 1985.

A fresh appeal, prompted by the release of the Guildford Four last year,
was suddenly adjourned last week after the court was told that in 1977 a
chance review of test kits by Home Office scientists had discovered that
some kits had been contaminated with explosives. The test kits contain swabs
and a solvent which police use to take samples from the suspects’ hands.
At the time, three laboratories were producing test kits: the Home Office,
the Metropolitan Police and the Royal Armament Research and Development
Establishment (RARDE). The solvent – ether – is believed to be the source
of the contamination.

To guard against contamination scientists always carry out a control
experiment. The control should repeat the experiment exactly, with the sole
exception of the test material. The scientist who conducted the original
tests on the Maguire Seven has since died. The 1976 trial was told he may
have used ether from a different source in his control experiment.

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Brian Caddy, director of the forensic science unit at the University
of Strath clyde, said it was ‘bad laboratory practice’ for the control not
to repeat the experiment exactly. He said that after the passage of so much
time it was difficult to pinpoint exactly what happened.

Caddy was one of the team of forensic scientists working on the evidence
for Sir John May’s inquiry into the cases of the Guildford Four and the
Maguire Seven. The May inquiry severely criticised the forensic evidence
which convicted the Maguire Seven.

Caddy explained that even a small amount of contamination in the ether
was likely to show up in the test, because the ether is evaporated to a
small volume, as little as 50 micro litres, concentrating the explosive.

The appeal court has already heard that a RARDE kit was found to be
contaminated with nitroglycerine. Other kits were found contaminated with
both nitroglycerine and another explosive, ethylene glycol dinitrate.

Caddy points out that the RARDE (now the Military Division of the Defence
Research Agency) also manufactured explosives and with ‘bulk supplies in
other buildings it had a particular problem’ in avoiding contamination.
Effective quality control was only coming in the middle 1970s, he says.

The contamination of the test kits has implications for other people
who were convicted of handling explosives in the 1970s and is likely to
result in other appeals. Caddy said he was ‘very sad and upset. This is
bringing forensic science into disrepute.’

The appeal court hearing into the Maguire case is continuing. The Director
of Public Prosecutions has already conceded that the convictions are not
safe.